Presentation is loading. Please wait.

Presentation is loading. Please wait.

Aldehydes and Ketones The functional group in aldehydes and ketones is the carbonyl group.

Similar presentations


Presentation on theme: "Aldehydes and Ketones The functional group in aldehydes and ketones is the carbonyl group."— Presentation transcript:

1 Aldehydes and Ketones The functional group in aldehydes and ketones is the carbonyl group.

2 Aldehydes and Ketones Except for formaldehyde, aldehydes have one H atom and one organic group bonded to a carbonyl group. Ketones have two organic groups bonded to a carbonyl group.

3 Aldehydes and Ketones Common names for aldehydes are derived from the name of the acid with the same number of C atoms. IUPAC names are derived from the parent hydrocarbon name by replacing -e with -al.

4 Aldehydes and Ketones The IUPAC name for a ketone is the characteristic stem for the parent hydrocarbon plus the suffix -one. A numeric prefix indicates the position of the carbonyl group in a chain or on a ring.

5 Amines Amines are derivatives of ammonia in which one or more H atoms have been replaced by organic groups (aliphatic or aromatic or a mixture of both). There are three classes of amines.

6 Carboxylic Acids Carboxylic acids contain the carboxyl functional group. The general formula for carboxylic acids is: –R represents an alkyl or an aryl group IUPAC names for a carboxylic acid are derived from the name of the parent hydrocarbon. –The final -e is dropped from the name of the parent hydrocarbon –The suffix -oic is added followed by the word acid. Many organic acids are called by their common (trivial) names which are derived from Greek or Latin.

7 Carboxylic Acids

8 Positions of substituents on carboxylic acid chains are indicated by numeric prefixes as in other compounds –Begin the counting scheme from the carboxyl group carbon atom. They are also often indicated by lower case Greek letters. –  = 1 st C atom –  = 2 nd C atom –  = 3 rd C atom, etc.

9 Nomenclature of Carboxylic Acids Dicarboxylic acids contain two carboxyl groups per molecule.

10 Carboxylic Acids Aromatic acids are usually called by their common names. Sometimes, they are named as derivatives of benzoic acid which is considered to be the "parent" aromatic acid.

11 Some Derivatives of Carboxylic Acids

12 Priority Functional groupFormulaPrefixSuffix 1 Cations e.g. Ammonium –NH 4 + -onio- ammonio- -onium -ammonium 2Carboxylic acids–COOHcarboxy--oic acid* 3 Carboxylic acid derivatives Esters Acyl chlorides Amides –COOR –COCl –CONH 2 R-oxycarbonyl- chloroformyl- carbamoyl- -oyl chloride* -amide* 4 Nitrites Isocyanides –CN –NC cyano- isocyano- -nitrile* isocyanide 5 Aldehydes Thioaldehydes –CHO –CHS formyl- thioformyl- -al* -thial* 6 Ketones Thioketones >CO >CS oxo- thiono- -one -thione 7 Alcohols Thiols –OH –SH hydroxy- sulfanyl- -ol -thiol 8Amines–NH 2 amino--amine 9 Ethers Thioethers –O– –S– -oxy- -thio- When compounds contain more than one functional group, the order of precedence determines which groups are named with prefix or suffix forms. The highest precedence group takes the suffix, with all others taking the prefix form. However, double and triple bonds only take suffix form (-en and -yn) and are used with other suffixes.

13

14 Isomerism Isomers have identical composition but different structuresIsomers have identical composition but different structures Two forms of isomerismTwo forms of isomerism –Constitutional (or structural) –Stereoisomerism ConstitutionalConstitutional –Same empirical formula but different atom-to-atom connections StereoisomerismStereoisomerism –Same atom-to-atom connections but different arrangement in space.

15 Structural Isomers

16 Cis-2-butene Stereoisomers: Geometric Geometric isomers can occur when there is a C=C double bond. Trans-2-butene

17 Optical isomers are molecules with non-superimposable mirror images. Such molecules are called CHIRAL Pairs of chiral molecules are enantiomers. Chiral molecules in solution can rotate the plane of plane polarized light. Stereoisomers: Optical Chirality generally occurs when a C atom has 4 different groups attached. Lactic acid

18 Chirality: Handedness in Nature These molecules are non-superimposable mirror images.

19 Sugars: Related to Alcohols Sugars are carbohydrates, compounds with the formula C x (H 2 O) y.Sugars are carbohydrates, compounds with the formula C x (H 2 O) y. What is the difference between a and b D-glucose?

20 Sucrose and Ribose Deoxyribose, the sugar in the DNA backbone.

21 Fats and Oils R = organic group with NO C=C bonds C 12 = Lauric acid C 16 = Palmitic acid C 18 = Stearic acid R = organic group with NO C=C bonds C 12 = Lauric acid C 16 = Palmitic acid C 18 = Stearic acid R = organic group with C=C bonds C 18 = oleic acid R = organic group with C=C bonds C 18 = oleic acid What is the functional group in a fat or oil?

22 Fats and Oils Fats with C=C bonds are usually LIQUDS Oleic acid: a monounsaturated fatty acid C=C bond

23 Trans Fatty Acids Oleic acid is a mono–unsaturated cis- fatty acidOleic acid is a mono–unsaturated cis- fatty acid Trans fatty acids have deleterious health effects.Trans fatty acids have deleterious health effects. Trans fatty acids raise plasma LDL cholesterol and lower HDL levels.Trans fatty acids raise plasma LDL cholesterol and lower HDL levels. C=C bond

24 Alpha-Amino Acids

25 Peptides and Proteins Adding more peptide links ---> PROTEIN – H 2 O

26 PolymersPolymers Giant molecules made by joining many small molecules called monomersGiant molecules made by joining many small molecules called monomers Average production is 150 kg per person annually in the U.S.Average production is 150 kg per person annually in the U.S.

27 Polymer Classifications Thermoplastics (polyethylene) soften and flow when heatedThermoplastics (polyethylene) soften and flow when heated Thermosetting plastics — soft initially but set to solid when heated. Cannot be resoftened.Thermosetting plastics — soft initially but set to solid when heated. Cannot be resoftened. Other classification: plastics, fibers, elastomers, coatings, adhesivesOther classification: plastics, fibers, elastomers, coatings, adhesives

28 Polymer Preparation Addition polymers — directly adding monomer units togetherAddition polymers — directly adding monomer units together Condensation polymers — combining monomer units and splitting out a small water (water)Condensation polymers — combining monomer units and splitting out a small water (water)

29 Types of Polyethylene Linear, high density PE (HDPE) Branched, low density PE, LDPE Cross-linked PE, CLPE

30 Types of Polyethylene Table 11.12: others are PVC, acrylonitrile, polypropylene, polymethyl methacrylate

31 Bubble Gum! A copolymer Styrene + butadiene

32 Condensation Polymers

33 Polyamides: Nylon Each monomer has 6 C atoms in its chain.Each monomer has 6 C atoms in its chain. A polyamide link forms on elmination of HClA polyamide link forms on elmination of HCl Result = nylon 66Result = nylon 66 Proteins are polyamidesProteins are polyamides

34 Polymer Recycling Symbols LDPE = Low density PE = 0.910-0.925 g/cm 3 HDPE = High density PE = 0.941-0.965 PP = Polypropylene = 0.90 V = PVC (Vinyl chloride) = 1.30-1.58


Download ppt "Aldehydes and Ketones The functional group in aldehydes and ketones is the carbonyl group."

Similar presentations


Ads by Google